Optical disk apparatus with pickup tilt adjusting mechanism and entertainment apparatus

ABSTRACT

A relative adjustment between an optical disc rotating mechanism and an optical pickup is adjusted by rotating a rotary member against a biasing force of an engaging projection. As the rotary member is rotated, the projection is slid for movement on an inclined surface, changing a relative position between the rotary member and a bottom wall of a subsidiary chassis, causing the subsidiary chassis to have a varied inclination relative to a main chassis. An adjusted condition is maintained by an engaging force between an engaging groove and the engaging projection biased toward the rotary member.

CROSS REFERENCE TO RELATED APPLICATION

The content of Application No. TOKUGAN 2000-354056 which was filed inJapan on Nov. 21, 2000 and on which the claim to priority for thisapplication is based, is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an optical disc apparatus in which anoptical disc is irradiated with a laser beam from an optical pickup, tothereby record and/or reproduce information, and an adjusting method foran optical disc apparatus, and further to an entertainment apparatusincluding an optical disc apparatus.

2. Description of the Related Art

The optical disc apparatus is provided with an optical disc rotatingmechanism and an optical pickup, for recording and/or reproducingoptical disc information, such as of a CD (compact disc), DVD (digitalversatile disc), CD-ROM (CD read-only memory), DVD-ROM (DVD read-onlymemory), CD-R (CD-recordable), and DVD-R (DVD-recordable). The opticaldisc rotating mechanism is adapted for supporting an optical disc, andthe optical pick up, for irradiating a signal recording side of theoptical disc by a laser beam.

SUMMARY OF THE INVENTION

Generally, the optical disc apparatus requires a laser beam to be normalto a signal recording side of an optical disc.

However, during production, the optical disc is subject to errors suchas when molding component parts or assembling parts together, with aresultant error also in respect of a relative position between anoptical disc rotating mechanism and an optical pickup, which may cause alaser beam failing to be normal to an optical disc.

For absorbing such production errors to enhance the normality of a laserbeam, there is a known method in which an optical disc rotatingmechanism is mounted on a main chassis and an optical pickup is mountedon a subsidiary chassis, and in which the main and subsidiary chassisare interconnected in a rotatable manner, allowing for the subsidiarychassis to be adjusted in inclination relative to the main chassis. Morespecifically, a spring is interposed between the main and subsidiarychassis, and a bolt inserted into the subsidiary chassis is screwed intoa threaded hole formed in the main chassis. Then, the bolt is driventight against resiliency of the spring, so that the subsidiary chassisis adjusted to have an appropriate inclination to the main chassis.After the adjustment, an adhesive is filled between the bolt and thehole, to thereby prevent rotation of the bolt.

However, as using an adhesive, this method inherently involvescomplicated work. Moreover, for the time to be secured for the adhesiveto become solid, it is difficult to reduce the production time, inaddition to the difficulty of readjustment after solidification of theadhesive.

The present invention is made with such points in view. It therefore isan object of the present invention to provide an optical disc apparatus,an adjusting method for an optical apparatus, and an entertainmentapparatus including an optical disc apparatus, with improved workabilityin adjustment for enhancement of the normality of a laser beam to anoptical disc, as well as in readjustment to be facilitated.

To achieve the object, according to an aspect of the present invention,an optical disc apparatus comprises a main chassis, a rotary memberhaving a plurality of first engagement parts, a subsidiary chassis, anelastic member, a projection, a spiral inclined surface, and a secondengagement part. An optical disc rotating mechanism is mounted to themain chassis. A rotation axis of the rotary member is held in a fixedposition relative to the main chassis, and the plurality of firstengagement parts are arrayed on a circular arc about the rotation axis.The subsidiary chassis supports an optical pickup to be slidable formovement, and is rotatably connected to the main chassis. The subsidiarychassis has an operating part disposed between the main chassis and therotary member. The elastic member is disposed between the main chassisand the subsidiary chassis, and biases the operating part of thesubsidiary member toward the rotary member. The projection is providedto one of the operating part of the subsidiary chassis and the rotarymember, to project toward the other thereof. The spiral inclined surfaceis provided to the other of the operating part of the subsidiary chassisand the rotary member, receiving a biasing force from the elasticmember, to be brought into pressing contact with the projection, and isconfigured, as the rotary member is rotated, to slidingly contact theprojection, changing a position of the operating part relative to therotary member. The second engagement part is provided to one of thesubsidiary chassis and the elastic member, biased toward the rotarymember, and configured for engaging with an arbitrary one of theplurality of first engagement parts to prevent rotation of the rotarymember.

For enhancement of a normality of a laser beam relative to an opticaldisc, an adjustment of a relative position between the optical discrotating mechanism and the optical pickup is performed by rotating therotary member against a biasing force of the second engagement part. Asthe rotary member is rotated, the projection is slid to move on theinclined surface, changing a relative position between the rotary memberand the operating part of the subsidiary chassis. Because the rotarymember is rotatably supported by the main chassis and its rotation axisis held in a fixed position relative to the main chassis, when therelative position between the rotary member and the subsidiary chassisis changed, an inclination of the subsidiary chassis to the main chassisis changed. As a result, the relative position between the optical discrotating mechanism and the optical pickup is adjusted, and the adjustedcondition is maintained by an engaging force between a first engagementpart and the second engagement part biased toward the rotary member.

The adjusted condition can be maintained without use of an adhesive,allowing for adjustment workability to be improved, as well asreadjustment to be facilitated.

An entertainment apparatus is provided with an optical disc apparatusaccording to the present invention.

Artisan will fully understand the above and further objects and featuresof the present invention by reading preferred embodiments of theinvention described herein in connection with the accompanying drawings,including features recited in the appended claims, as well as explicitand implicit effects and advantages of the invention, including those tobe apparent through implementation of the invention.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

FIG. 1 is a perspective view in appearance of an entertainment apparatusincluding an optical disc apparatus according to a first embodiment ofthe present invention.

FIG. 2 is a plan view of the optical disc apparatus.

FIG. 3 is a plan view of a main chassis of the optical disc apparatus.

FIG. 4 is a plan view of a subsidiary chassis of the optical discapparatus.

FIG. 5 is an exploded perspective view of the optical disc apparatus.

FIG. 6 is a front view of the optical disc apparatus.

FIG. 7 is a sectional side view of the optical disc apparatus.

FIG. 8 is a perspective view of a rotary member of the optical discapparatus.

FIG. 9 is a detailed view of an essential portion of the optical discapparatus, showing engagement between an engaging projection and anengaging groove.

FIG. 10 is a sectional view of an essential portion of an optical discapparatus according to a second embodiment of the invention.

FIG. 11 is a sectional view of an essential portion of an optical discapparatus according to a third embodiment of the invention.

FIG. 12 is a perspective view of an essential portion of a subsidiarychassis of the optical disc apparatus of FIG. 11.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Various embodiments of the present invention will be described withreference to the accompanying drawings. It is noted that like parts orelements are designated by like reference characters in the drawings,without redundant description of the parts or elements.

The present invention is applicable to an entertainment apparatus thathas a game executing function for executing a video game based on a gameprogram recorded in an optical disc, such as a DVD-ROM or CD-ROM, and animage reproducing function for reproducing information on an image, suchas a picture image, recorded in the optical disc.

First Embodiment

FIG. 1 shows, in perspective view of appearance, an entertainmentapparatus according to a first embodiment of the invention. Theentertainment apparatus is equipped with an apparatus body 1 such as forexecution of a video game or reproduction of a picture, and a controller20 connected to the apparatus body 1.

Arrangement of Apparatus Body

The apparatus body 1 has a pair of USB (universal serial bus) connectionterminals 2 connectable to USB-oriented apparatuses, an optical discapparatus 3 of a tray type to which an optical disc 12, such as a CD-ROMor DVD-ROM, having recorded an application program of a television gameor multi-medium data such as of a picture can be set, a reset button 4for resetting a game, an IEEE1394 connection terminal 5 which can copewith a data transfer rate of e.g. 400 Mbps at maximum, a tray operationbutton 6 for operating a disc tray (not shown) of the optical discapparatus 3 to go in and out, controller connecting parts 7A and 7B, andmemory card application parts 8A and 8B.

The apparatus body 1 is provided at the backside with a power switch(not shown), AV terminals (not shown) for connecting the apparatus body1 to a monitor 9 or audio device (not shown), and the like.

The controller connecting parts 7A and 7B, two in number, are eachrespectively connectable to a connector 11 of the controller 20. Thememory card application parts 8A and 8B are for application of a savingmemory card 10 for game data to be saved (stored) therein and readtherefrom, a DVD driver memory card (not shown) in which a driverprogram for DVD reproduction is stored, and the like.

Arrangement of Optical Disc Apparatus

The optical disc apparatus 3 is provided, as shown in FIG. 2 to FIG. 6,with a main chassis 30, a subsidiary chassis 31, an optical discrotating mechanism 32 for driving the optical disc 12 into rotation, anoptical pickup 33 for reading a signal from the optical disc 12, and asledding mechanism 34 for moving the optical pickup 33 in a radialdirection of the optical disc 12. The optical disc apparatus 3 furtherhas, though not shown, a disc tray for the optical disc 12 to be mountedthereon, a loading mechanism for letting the disc tray go into and outof the apparatus body 1, and a mechanism for moving the optical discrotating mechanism 32 and the optical pickup 33 toward the disc trayupon loading. It is noted that the optical pickup 33 may be adapted forsignal writing and reading to and from the optical disc 12.

As shown in FIG. 3 and FIG. 6, the main chassis 30 is made by a metallicplate punched in a specified form and bent into a frame configuration,which has its one end part 30 a and the other end part 30 binterconnected by a pair of connecting parts 30 c and 30 d.

The optical disc rotating mechanism 32 has a spindle motor 34 forrotating the optical disc 12 and a turn table 36 fixed to a spindleshaft (not shown) of the spindle motor 34, and is mounted at the one endpart 30 a of the main chassis 30.

The two connecting parts 30 c and 30 d of the main chassis 30 are formedwith shaft supporting parts 39 and 40 for rotatably supportinglater-described rotation shafts 37 and 38 (shown in FIG. 4 and FIG. 6)of the subsidiary chassis 31. The shaft supporting part 39 is formedwith a groove 41 for receiving the rotation shaft 37, projections 45 forpositioning a later-described slip-out preventing member 43, andthreaded holes 49 for screwing bolts 47 to fix the slip-out preventingmember 43. The shaft supporting part 40 is formed with a groove 42 forreceiving the rotation shaft 38, holes 46 for positioning alater-described slip-out preventing member 44, and threaded holes 50 forscrewing bolts 48 to fix the slip-out preventing member 44.

As shown in FIG. 4, the subsidiary chassis 31 is made by a projectionmolded hard resin of a frame configuration, which has its one end part31 a and the other end part 31 b interconnected by a pair of side walls31 c and 31 d.

The rotation shafts 37 and 38 are integrally formed on, as projectionsfrom, outsides of the two sidewalls 31 c and 31 d of the subsidiarychassis 31. As shown in FIG. 2, FIG. 5, and FIG. 6, the rotation shafts37 and 38 accommodated in the grooves 41 and 42 are rotatably supportedbetween the shaft supporting parts 39 and 40 and the slip-out preventingmembers 43 and 44. As shown in FIG. 5, one slip-out preventing member 43has holes 51 for insertion of the projections 45 for positioning theshaft supporting part 39, and holes 52 for insertion of the bolts 47.The other slip-out preventing member 44 has projections 53 to beinserted into the holes 46 for positioning the shaft supporting part 40,and holes 54 for insertion of the bolts 48. The rotation shafts 37 and38 intersect later-described guide rails 55 and 56 substantially atright angles, and received in the grooves 41 and 42, extendingsubstantially in parallel with a recording side of the optical disc 12.

As shown in FIG. 2 and FIG. 4, the sledding mechanism 34 is providedwith a pair of guide rails 55 and 56, a carriage 57, a sled motor 58, adrive rod 59, and a connecting rack 60. The guide rails 55 and 56 aresupported at their both ends by the one end part 31 a and the other endpart 31 b of the subsidiary chassis 31. The carriage 57 is supported tobe slidable for movement along the guide rails 55 and 56. The opticalpickup 33 is mounted on the carriage 57. The guide rails 55 and 56 areconfigured for restricting the direction of movement of the carriage 57to cause an objective lens 33 a of the optical pickup 33 to move in aradial direction of the optical disc 12. The drive rod 59 has a spiralgroove in the outer circumferential surface, and is disposedsubstantially in parallel with the guide rails 55 and 56, to bedirect-coupled to the sled motor 58. The connecting rack 60 is connectedat one end thereof to the carriage 57, and engaged at the other end withthe groove of the drive rod 59. Rotation of the sled motor 58 istransmitted to the carriage 57 via the drive rod 59 and the connectingrack 60, thereby moving the carriage 57.

As shown in FIG. 5, the other end part 31 b of the subsidiary chassis 31has a bottom wall 61 as an operating part opposing the other end part 30b of the main chassis 30. Between the bottom wall 61 of the subsidiarychassis 31 and the other end part 30 b of the main chassis 30 isinterposed a plate spring 63 as an elastic or resilient member. A shaftbody 62 as a substantially cylindrical metal is fixed to the other endpart 30 b of the main chassis 30. The shaft body 62 is inserted at thedistal end into a hole 67 formed in the bottom wall 61 of the subsidiarychassis 31.

A distal end face 62 a of the shaft body 62 is formed with a threadedhole 64, and a bolt 65 screwed to the threaded hole 64 cooperates withthe distal end face 62 a to have a rotary member 66 rotatably supportedtherebetween. In other words, a rotation axis of the rotary member 66 isheld in a constant or fixed position relative to the main chassis 30, sothat the rotary member 66 is rotatably supported in position spaced at aspecified distance from the other end part 30 b of the main chassis 30opposing the bottom wall 61.

As shown in FIG. 7 and FIG. 8, the rotary member 66 has a substantiallyannular gear 68 placed on the distal end face 62 a of the shaft body 62,and a cam 69 integrally formed on the gear 68 so as to extend therefromalong an outer circumferential surface of a diameter-reduced distal endpart of the shaft body 62. The cam 69 is formed with a distal end faceconstituted as a helical inclined surface 70 spaced at gradually varyingdistances from the gear 69 (i.e. at gradually varying heights from theother end part 30 b of the main chassis 30). The inclined surface 70 isformed substantially within a range of 360°, such that its one end 70 anearest to the gear 68 and the other end 70 b farmost from the gear 68neighbor each other. As shown in FIG. 2 and FIG. 9, the gear 68 has aplurality of engaging grooves 71 consecutively ring-like formed as afirst engagement portion in an outer circumferential surface thereof. Inother words, the engaging grooves 71 are arrayed on a circular arc aboutthe rotation axis of the rotary member 66. The bottom wall 61 of thesubsidiary chassis 31 is interposed between the other end part 30 b ofthe main chassis 30 and the rotary member 66.

The plate spring 63 has a base 72 placed on the other end part 30 b ofthe main chassis 30, a spring piece 73 folded back at one end of thebase 72, and an extended part 74 bent at the other end of the base 72 toextend toward the rotary member 66. The base 72 has a hole 75 forinsertion of the shaft body 62, and a hole 76 for insertion of apositioning projection 77 projecting from the other end part 30 b of themain chassis 30. The plate spring 63 is held in a specified position byinserting the shaft body 62 and the projection 77 into the two holes 75and 76. As shown in FIG. 7, the spring piece 73 is bent at the distalend so as to project toward the bottom wall 61 of the subsidiary chassis31, for biasing the bottom wall 61 toward the rotary member 66. As shownin FIG. 9, a distal upper part of the extended part 74 is bent towardthe rotary member 66, to be folded back to provide a doubled distalpart, and this doubled part is transversely folded in a wavy form with alongitudinally extending transversely central engaging projection 79 asa second engagement part that is lockingly engageable with an arbitraryengaging groove 71 of the rotary member 66. The engaging projection 79is biased toward the engaging groove 71 by resiliency of the extendedpart 74, so that locking engagement between the engaging projection 79and the engaging groove 71 is maintained by a resilient biasing force.It is noted that the rotary member 66 may be formed with a plurality ofengaging projections and the plate spring 63 may be formed with anengaging groove lockingly engageable with an arbitrary one of suchprojections.

The bottom wall 61 of the subsidiary chassis 31 is integrally formedwith a projection 80 projecting toward the inclined surface 70 of therotary member 66. As the bottom wall 61 receives a biasing force fromthe plate spring 63, the projection 80 is brought into pressing contacton the inclined surface 70. Under such a condition, as the rotary member66 is rotated, the inclined surface 70 slidingly contacts the projection80, so that the bottom wall 61 has a changed position relative to therotary member 66.

Adjusting Method of Optical Disc Apparatus

For enhancement of the normality of a laser beam to the optical disc 12,an adjustment of a relative position between the optical disc rotatingmechanism 32 and the optical pickup 33 is performed by rotating therotary member 66 against a biasing force acting from the extended part74 of the plate spring 63 on the engaging projection 79. As the rotarymember 66 is rotated, the projection 80 is slid for movement on theinclined surface 70, changing a relative position between the rotarymember 66 and the bottom wall 61 of the subsidiary chassis 31. Becausethe rotation axis of the rotary member 66 is held in a fixed positionrelative to the main chassis 30, as a relative position between therotary member 66 and the subsidiary chassis 31 changes, the subsidiarychassis 31 has a changed inclination relative to the main chassis 30,allowing for the relative position between the optical disc rotatingmechanism 32 and the optical pickup 33 to be adjusted. After theadjustment, the relative position is maintained by an engaging forcebetween the engaging groove 71 of the gear 68 and the engagingprojection 79 biased toward the rotary member 66.

Like this, according to the present embodiment, a relative positionbetween the optical disc rotating mechanism 32 and the optical pickup 33can be maintained with ease without using an adhesive, allowing foradjustment workability to be improved, as well as readjustment to befacilitated.

Moreover, the engaging projection 79 is integrally formed on the platespring 63, allowing for the number of components to be reduced and thestructure to be simplified. Further, the engaging projection 79 isbiased toward the engaging groove 71 by resiliency of the plate spring63, causing a strong engagement therebetween, allowing for a adjustedcondition to be maintained firm.

Still more, the inclined surface 70 is formed substantially within arange of 360° such that its one end 70 a nearest to the gear 68 and theother end 70 b farmost from the gear 68 neighbor each other, and aplurality of engaging grooves 71 are consecutively ring-like formed inan outer circumferential surface of the cam 69, whereby the range ofadjustment is widen, allowing for fine adjustment to be coped with.

Second Embodiment

FIG. 10 shows a second embodiment of the present invention, which isdifferent from the first embodiment in that a projection 81 projectsfrom a gear 68 of a rotary member 66, and a cam 83 is formed with aninclined surface 82 on a bottom wall 61 of a subsidiary chassis 31.Other arrangements of the second embodiment are similar to the firstembodiment.

The second embodiment has like effects to the first embodiment.

Third Embodiment

FIG. 11 and FIG. 12 show a third embodiment of the present invention,which is different from the first embodiment in that in place of theplate spring in the first embodiment a coil spring 84 is interposed asan elastic or resilient member between a main chassis 30 and a bottomwall 61 of a subsidiary chassis 31 and in that in place of the engagingprojection integrally formed on the plate spring in the first embodimentan engaging projection 89 as a second engagement part is integrallyformed on the subsidiary chassis 31. Other arrangements of the thirdembodiment are similar to the first embodiment.

In the vicinity of an engaging groove 71 of a rotary member 66, there isdisposed a connecting part 88 of a substantially U-form integrallyconnected at both ends thereof to opposite walls 86 and 87 of an endpart 31 b of he subsidiary chassis 31, while the connecting part 88 hassubstantially at the center an engaging projection 89 integrallyextending therefrom for engagement with the engaging groove 71. Theengaging projection 89 is engaged with the engaging groove 71, to bedisposed in a slightly flexed position, in a condition biased toward theengaging groove 71.

The third embodiment does not need an adhesive in adjustment work, likethe first embodiment, thus allowing for the workability to be improved,as well as readjustment to be facilitated.

It is possible to have a reduced number of components and a simplifiedstructure, with a wide adjustment range, coping with fine adjustment aswell.

Provision of the engaging projection 89 independent from a resilientmember allows for the resilient member to be designed free fromlimitations such as to material and configuration.

As will be seen from the foregoing description, according to the presentinvention, an optical disc apparatus can be maintained in an adjustedcondition without use of an adhesive, allowing for the workability to beimproved, as well as readjustment to be facilitated.

While preferred embodiments of the present invention have been describedusing specific terms, such description is for illustrative purposes, andit is to be understood that changes and variations may be made withoutdeparting from the spirit or scope of the following claims.

What is claimed is:
 1. An optical disc apparatus comprising: a mainchassis; an optical disc rotating mechanism mounted to the main chassis;a rotary member having a rotation axis held in a fixed position relativeto the main chassis, and a plurality of first engagement parts arrayedon a circular arc about the rotation axis; a subsidiary chassisrotatably connected to the main chassis, the subsidiary chassis havingan operating part disposed between the main chassis and the rotarymember; an optical pickup supported by the subsidiary chassis, to beslidable for movement; an elastic member disposed between the mainchassis and the subsidiary chassis, the elastic member biasing theoperating part of the subsidiary member toward the rotary member; aprojection provided to one of the operating part of the subsidiarychassis and the rotary member, to project toward the other thereof; ahelical inclined surface provided to the other of the operating part ofthe subsidiary chassis and the rotary member, the inclined surfacereceiving a biasing force from the elastic member, to be brought intopressing contact with the projection, the inclined surface beingconfigured, as the rotary member is rotated, to slidingly contact theprojection, changing a position of the operating part relative to therotary member; and a second engagement part provided to one of thesubsidiary chassis and the elastic member and biased toward the rotarymember, the second engagement part being configured for engaging with anarbitrary one of the plurality of first engagement parts to preventrotation of the rotary member, so that, once the rotary member isrotated against a biasing force of the second engagement part, havingthe projection relatively slid to move on the inclined surface, with achanged relative position between the rotary member and the subsidiarychassis, the relative position between the rotary member and thesubsidiary chassis is held by an engaging force between the secondengagement part and the arbitrary first engagement part.
 2. The opticaldisc apparatus as claimed in claim 1, further comprising: a hole formedin the operating part of the subsidiary chassis; and a shaft bodyextending from the main chassis and inserted into the hole, the shaftbody supporting the rotary member to be rotatable.
 3. An entertainmentapparatus provided with an optical disc apparatus according to claim 2.4. The optical disc apparatus as claimed in claim 1, wherein the rotarymember has a substantially annular gear and a cam, the plurality offirst engagement parts are consecutively ring-like disposed on an outercircumferential surface of the gear, and the cam is integrally extendedfrom the gear to form the inclined surface.
 5. An entertainmentapparatus provided with an optical disc apparatus according to claim 3.6. The optical disc apparatus as claimed in claim 1, wherein the elasticmember comprises a plate spring, and the second engagement part isintegrally formed with the plate spring.
 7. An entertainment apparatusprovided with an optical disc apparatus according to claim
 6. 8. Theoptical disc apparatus as claimed in claim 1, wherein the secondengagement part is integrally formed with the subsidiary chassis.
 9. Anentertainment apparatus provided with an optical disc apparatusaccording to claim
 8. 10. An entertainment apparatus provided with anoptical disc apparatus according to claim 1.